Cable splice testing apparatus



Jan. 3, 1950 I c. E. LEWIS 2,493,077

CABLE SPLICE TESTING APPARATUS Filed Jan. 17, 1946 3 Sheets-Sheet 1 lNl/EA/ TOR a. 5 LEW/S A 7" Tom/5y Jan. 3, 1950 c. E. LEWIS 2,493,077

CABLE SPLICE TESTING APPARATUS Filed Jan. 17, 1946 I5 Sheets-Sheet 2 lM/ENTOR (J. E. LEW/5 8V ATTORNEY Jan. 3, 1950 c. E. LEWIS 2,493,077

'GABLE SPLICE TESTING APPARATUS Filed Jan. 17, 1946 3 Sheets-Sheet 3 lA/VE/VTOR FIG. 5. I c. E LEW/S BY ATTOQA/gv Patented Jan. 3, 1950 CABLE SPLICE TESTING APPARATUS ,Glay E. Lewis, Baltimore, Md., assignor to Westn E t c C m a o rated, Ne York, N. Y., a corporation of New York Application January =17, 194.6, Serial NQ.;64;1 ,:84 9

1 Claim.

T i ven i n helates to test n apparatus and more particularly to apparatus for testing cable splices.

In the manufacture of multi-conductor electric cables, it is often necessary to splice normally manufactured lengths Lof cable together in order to form a cable whose length conforms to specific manufacturing specifications or is suitable :for a particular field installation in which the cable is torbe used. Cable splices .are also necessitated by the fact that "when insulation faults are detected in such cables :the faulty portion must be removed from the cable and :the ends thereof spliced together.

Various types .of splices .are employed in joining two lengths .of cable, however, the :present invention is related to the testing of a particular type which is formed bytbutting the ends of the individualconductorsof the cableandlcausing a small amount of silver solder, or the like, to flow around the joint and join the vends thereof together. When the splice is completed, it is usually sub.- jected to certain mechanical and electrical tests to determine whether the splice has been made properly and whether it :will remain intact during normal handling in the field. The mechanical testing of such :cable splices comprises flexing the splice while itis under tension, whereby substantial stresses are applied to :the welded joints of the splice. If the welded joints are improperly formed they will breakapartduring the flexing test, which fact may be determined by having a simple continuity i-test set connected to the ends of the spliced cable during the flexing test.

An-object of the invention-is to-provide newand improvedapparatustor testing cables.

Another object of the invention is to provide new and improved apparatus for automatically fl ing a .cahl ..snl e pred term ne er of s l as deel vctio o .acab espllce c dhg a p u embodying theinv nt on;

i 5 a i emehta v l n t h 9 .991- ion h driving me han sm show i Fie- 3, a e imm the r h dsid 9 that elhte Fla 3 i an n a e ho izo secti n iew r .a p rtion of the a pMaths taken alpha he line ,3-.-3 of Fig. 1

Eis-

s a e g d sec ona iviewhf smiths of th appa a u t ke alo line w F e "3." and hi :5 is a sch matic w in dia am c h mam hir uit- Reierring-SD Qifica11y= the draw n s and h t u a v to i the ergn atus h wh the in camp es a M d fh to wh h s c ve ed wi hnas e plate 1 n as ou ed-the eon? ench l?- A me e 3 is sco ted to the l hdc s de o t bench and i direct on e ted {to a gear reduc,er I4 also secured 91 the initia side o th hehc 4.2,-

ch hut-shafi l o the gear reducer 14 has a sprocket l6 keyed thereon and serves to drive a sprocket 11 Jay means of a roller cha f he sp c he I1 i sh cd w e cra k t 4. wh c is ro a e-W moun ed i hair .o he r ng 5 9:2" \WH Qh re i dly sc nt d to the p ate i E l c shank sh ft 1 .hasesmtk :21 seized 1QI.. ;QIl h t en-set the the end 91 which is pro ided w th a crank hi 122- h co necting rod 23 has one end thereof qtataply Qqsir l ione io th cran hind?- ill eiothc lehshp rt connecting rod 3 11s rctatablvsc h edito acr ss- ?head spin mounted 101 5 c qsshead which a r :slida y positioned zini'a slide 2 :5- frlzhe sl de is ri idly sec ed to a column 1 :1 --.which is mo nted iman upright positionmn-athemlate Isl zadsiaceri to theibench lhes de $5 issoan s tioncdion the column :21, that when the ,crank 4 sis in the r iil line ositionlshown onithe drawin :the lcrosshead is raised to the upperendsofrthesllde :bylthe connecting rod Whenathe ;crank 12;! zis rotated to :theibroken line :positionshown onthedrawing, :thesconnecting rod 323 carries the .crosshead s25 e120 the-lowenendof the slide 26.

Av grooved pulley 284s .rotatablyvpositionedjonia shaft :rigidlyrmounted .on the upper. endof sthe column- 2 'l. dllhe diameternf ethe .pulley 2 6 isisuch :that the center .line of the groove therein iiS sub.-

stantiall'y inlline withathelcenter line ofithe cross- :head -25-and theslide 2 6.

A suitable cable grip, such as a cable grip 3| (Figs. 3 and 4), is rigidly secured to the crosshead 25. The grip 3| is substantially identical with the one described and claimed in copending application Serial No. 529,518, filed April 4, 1944, by O. G. Nelson.

The cable grip 3| (Figs. 3 and 4) comprises a stationary block 32 and a movable block 33, each of which has a semicircular opening 34 provided in one face thereof and extending the entire length of the block, said openings 34-34 being provided with a plurality of semicircular serrations 35-35 (Fig. 4) The semicircular openings 34-34 have rubber inserts 36-35 moulded therein whereby the serrations 35-35 serve to firmly secure the inserts 36-36 in the openings 34-34. Each of the rubber inserts 35-36 has a semicircular groove 31 moulded therein and extending the entire length of the insert 36. The blocks 32 and 33 have slots 38-38 milled in each side thereof for the full depth of the block, and a plurality of bores 39-39 drilled therein which connect with the slots 38-38.

The blocks 32 and 33 are assembled as shown in Fig. 3, so that the inserts 35-35 are adjacent to each other, whereby the semicircular grooves 31-31 therein are aligned to form a split bore therethrough. The stationary block 32 is rigidly secured to the crosshead 25 and has the movable block 33 hingeclly attached thereto by means of a of the link 42 is circular in cross-section and is threaded to receive a tightening lever 45. When the movable block 33 is maintained in its closed position (Fig. 3) with respect to the stationary block 32, the semicircular grooves 31-31 of the rubber inserts 36-36 form a split bore whose diameter is adjustable by means of the tightening lever 45.

There is also positioned on the plate II a hollow, sheet steel guide 46 of rectangular crosssection, in which a weight 41 is slidably positioned. The weight 41 is provided with a steel bracket 48 on its upper end to which a cable grip 49 is secured. The cable grip 49 is identical with the cable grip 3| secured to the crosshead 25 and described hereinabove.

A weigh lifting mechanism 50 also is mounted on the plate H and comprises a treadle arm rotatably mounted on a bearing 52 by means of a pin 53 positioned in the bearing 52. The treadle arm 5| extends beyond the bearing 52 into the weight guide 46 and has a pad 54 movably positioned on the end thereof. A spring 56 is positioned between the treadle arm 5| and the plate H in order to maintain the weight lifting mechanism 50 in its normal position.

The weight lifting mechanism 50 is designed to be actuated by the foot of an operator and serves to lift the weight a substantial distance above the platform I 0 so that when the crosshead 25 is in its uppermost position as shown on the drawing, the weight 41 may be clamped to the left hand portion of a spliced cable 60 looped over the grooved pulley 28 and having a portion of its right hand side clamped in the cable grip 3| secured on the crosshead 25. The spliced cable 60 is made up of two lengths of multi-conductor cables 6| and 52 which are joined by a splice 63.

The spliced cable is looped over the pulley 28 (Fig. 1) so that the upper end of the splice 63 formed therein engages the left hand side of the pulley 28 when the crosshead 25 is in its uppermost position on the slide 26. When the crosshead 25 is moved to its lowermost position, the splice 63 will (be drawn around the periphery of the pulley 28 and assume a position on the right hand side of the pulley 28 shown in the broken lines on the drawing (Fig. 1). In other words, each time the crosshead 25 moves from its uppermost position to its lowermost position or vice versa, the splice 63 of the cable 60 is drawn around the periphery of the pulley 28 whereby the splice 63 is bent around the pulley 28 approximately 180. This flexing or bending of the splice 63 tends to fracture or break open improperly welded joints of the conductors of the spliced cable 60.

A ring 15 is adjustably positioned on the hub of the sprocket l1 and has threadedly mounted therein a round headed bolt 16. The ring 15 and the bolt 16 secured thereon are orientated with the crosshead 25 so that when the motor 3 is deenergized after a given flexing operation of the splice 63 the crosshead 25 always comes to rest at approximately the upper end of the slide 26. A super sensitive switch 80 is mounted on a bracket 8| secured to one of the bearings 20-20, and has an operating arm 82 aligned with the ring 15 and the bolt 16 carried thereby. When the sprocket I1 is rotated, the ring 15 secured on the hub thereof is rotated, whereupon the head of the bolt 16 mounted thereon strikes the arm 82 of the super sensitive switch 80.

There is positioned on the top of the bench |2 a test set 85, which contains the electrical apparatus used to automatically control the operation of the motor l3 which drives the flexing apparatus shown in Fig. 1. A pair of leads 86-86 extend from the test set and have a pair of connectors 81-81 provided on their ends, which are rigidly secured to an angular support 88 mounted on the bench l2 adjacent to the test set 85. A pair of connectors 89-89 provided on the ends of the spliced cable 60 are similar to the connectors 81-81 but are of the opposite hand thereto so that they may be inserted into the connectors 81-81 of the test set leads 86-86. The test set 85 is provided with a control panel 90 on which is positioned a plurality of indicating lamps 9|-9|, a push button 92 associated with the indicating lamps, a start push button 93 and a stop push button 94.

The apparatus contained in the test set 85 and used in conjunction with the cable splice flexing apparatus shown in Fig. 1 is described and claimed specifically in copending application Serial No. 641,848, filed January 17, 1946, by R. D. Gambrill, now Patent No. 2,479,920, granted Aug. 23, 1949.

The apparatus contained in the test set 85 is shown in schematic form in Fig. 5 of the drawings, wherein a pair of volt A. C. control busses I00 and I0! serve to supply potential to the continuity indicating circuit, and the motor control circuit.

As is shown in Fig. 5, the push button 92 is connected across the control busses I00 and |0| at junctions 03 and I04, respectively, and has connected in series therewith a primary winding I05 of a'potential transformer |06. A secondary winding |01 of the transformer |06 has one side thereof connected directly to a plurality of individual conductors ||3-||3 of the multi-con- 3? (meter cable 62 of 'the sp'liceds cable so". The multi-conductor cable BI referred to. hereinafter comprises four individuallyinsulated conductors III-I I I enclosed by ametalllcbraid IIO, which in turn has applied thereover an insulating jacket H2- The other side. of' the secondary winding I01 of the. transformer I06 is connected. to; one. side of each of the indicating; lamps; 9;I-'-9I-.. Each of the indicating. lamps 0.I::-9I has its opposite sides connected. to the. plurality of conductors I'I II-II of the multi condiictor' cable 6| which is identical in construction. with the. cable 6|. The spliced cable 60. contains the; splice 63 in which. the. conductors I:I.-I.'-I H. of; the cable 6| and: the conductors. I.I.-3i--I.I3Lof'the cable 62 have been. butt-welded by means; of silver solder, or the like, and the. respective joints; have thereafter been individually insulated and'enclosedin a braided metallic sleeve',.o.Ver which is: placed an outer insulating jacket made 01' a. material similar to that used in the; jacket I I2. of: the cable 6|.

When the push button 92 is closed the potential transformer I06 is energized whereupon the individual parallel circuits. comprising the indicatinglamps 9I--9'I.,,the conductors I'I-I'-'I I! and II3I I3 have impressed thereacross a' potential sufiicient to cause the indicating, lamps 9I9I to glow, providing there: are; no: breaks. or; defects in the joints between. the. individual conductors within the splice 63.

A normally open contact. I I5 of the-start-push button 93 has one side,- thereoti connected to a junction H6 on the bus I00 and the other side thereof connected to a normally closed: contact of the stop push button. 9\4:, which in;t.urn is connected to, a normally closed contact. I of a. control relay I2'I. The other side of. the normally closed contact I20 is: connectedtaan operating coil I22 of a magnetic relay I23 and has its other side connected directly to. the. control bus IOI at a junction I 24.. A normally; closed contact I25 of the push button 93 hasone side thereof con.- nected to azjunction I26 on. the control bus" I00 and has its other side; thereof. connected directly to a. normally open.contact, I21 on therelay I 2I. The other side of the contact}?! is connected; tov a; junction I30, which in turn is connected to a coi1 I:3.I of, the relay I2I connected to ajunction I32. on the-bus. IN. A normally open contactarm I33 hasone-side thereof connected directly to the-bus I00: at a junction I34 and the. other sidethereof connected to a junction I35 positioned between. the. normally :1

open contact II5 of the pusnbutton 93 and the normally closed contactof. the. push. button 94. The normally open. contact. I33- serves to bridge the normally open. contact H5. or; the starting push button 93am maintain the, relay I23 energized until the control circuit. associated. there"- withis interrupted by operationor; the relay I2 I. The stop push button. 94 is inserted. in the circult of the coil I22 as. asafety feature, whereby the apparatus may. be stopped at any time during its operation.

A junction I36- on thebus I00 is connected directly to a moving arm I31 or; a conventional type of step selector. I40; The junction I is also connected. to. a final. contact I24I. of. a plurality of contacts I4I--l4.I associated. with the arm I31 of the step selector. I I0.. A. filament transformer I42 has its primary-winding. I 43. connected directly across the; control busses- I00 and .IOI at junctions I46 and I4i,. respectively. A-

secondary winding I 46 ofthe filament transform or M1 is connected directly across fllaments I41- I41 of 'apair of rectifier tubes I-48I48. Each 01' the rectifier tubes Mil-I48 is provided with a filament I41, and a pair'of'anodesor plates I50 i50. Eachv of the plates I50-i--If50 is connected directly to one end of a resistor I 5I anclall of the resistors I5I I5I have; their opposite ends connected together andtoe junction: point I52. The junction point IE2 is connected toa resistor I53 connected toanother resistor I54, which. in turn isadjustably'connected to an: operating coi1 I 'of the stepselector m0. Therectifier tubes 8-! 48 and their associated resistors I 5I- I 5I, I53 and I54 serve to supplythe D. Qpotential necessary to operatethe step selector I40;

The other side of the coil I55 is connected to succeeding contacts I56'-- -I 50 andv to a norinalliy closed contact arm I51, the other side of which is connected to a final contact I58 of the step selector I46. A plurality of contacts- I50-I59 are positioned adjacent to and: horizontally aligned withv the contacts l156-I56; Another final? contact. I69 is. positioned adjacentt'o and horizontally aligned with. the final: contact. I58. The step selector M0 is provided with a movable arm I6I': connectedv to: the arm I31, and. both the arm I31 and the armv I 6:-I. are operated simultaneously when the. coil: IE5 is; energized; The contact-arm I5?! is aIsooDened-leach time: the coil I55. isenergizedby the D, C. circuit. The arm I31: serves to successively engage the: contacts MII4.II while the arm I.6I servesztosuccessively bridge across; apair of contacts consistingv of one right hand contact I56 and one. left hand contactv I59 and across the final'i contacts I58 and A junction point I 62 on. the. bus I0;I is con.- nected directly to a variable resistor I63 which in turnis connected to a junction. I64 and thence to the final. contact I of the step selector I40. The junction I64 is also connected toa condenser I65 which is connected to. another condenser I66 which in turn is connected: tothe. junction I52. The. contact arm- I5! of the step selector I40; is provided with a spring I61 which maintains the arm. I51 in, a normally closedposition. A junction point I10, positioned between thev junction point I65 and the final: contact I60, is connected to a normally openmicroswitch which. in turn is connected tothe contacts I59-I59 of the. step selector M0. The.-microswitch- 80 is actuatedby the round-headed bolt I6 positioned on the ring 15: which in turn is indirectly driven by the. motor I3. A source of A. C. potential is connected to a three-pole switch I15; connected to. three normally open contacts II.6-I.I6-of the: magnetic contactor I23, which in. turn are connected. to the motor I3; 7

The operation of. this apparatusisas follows:

Assuming that the crosshead- 25 is positioned at the'top of the slide 26, thespliced cable 60 is looped over the grooved pulley 28 so that. the splice 63' which is. to be tested by the apparatus is positioned on the. lefthand side of the pulley .28. The cable length 62 of the spliced cable 60, which. is. positioned on the right hand side of the pulley 28, is placed in thercable grip I mounted on, the crosshead. 25. and'firmly held therein by turning the lever 45 so as to squ'eeze the cable 62in the split bore provided :bythe inserts 36--3.6. The spliced cable 60 is held in. a substantially taut position whereupon the treadle arm 5|; is

'depressedtolift the weight; 41 a substantial dis.-

.tance above; the.- platform: I0, T-hQFCBvbIBT length 62, which is below the splice 63, is placed in the cable grip 49 and firmly secured therein by turning its lever 45. The treadle arm I is now released, whereupon the weight 41 is carried entirely by the spliced cable 60 and serves to exert a substantial tension on the individual welded joints within the splice 63.

Having secured the spliced cable 60 in the cable grips 3| and 49, the connectors 89-89 of the cable are inserted into the connectors 8181 of the test set 85. The spliced cable 66 is now connected to the continuity indicating circuit (Fig. 5) whereupon the push button 92 associated therewith is actuated to close the energizing circuit of the transformer I96, thereby causing the indicating lamps 9I9I to glow, which fact indicates that the conductors IIII II of the cable length BI are now making good electrical contact with the conductors II3I I3 of the cable length 62.

The push button 62 is maintained in the closed position and the'start push button 93 is actuated, thereby closing the circuit to the operating coil I22 of the magnetic contactor I I. When the coil I22 is energized it closes its control contact I33 and its motor circuit contacts I16-I16. The contact I33 provides a holding circuit for the coil I22 so that the push button 93 may be released after the contact I33 has closed. Assuming that the three-pole switch I15 is closed, the contacts I16I16 serve to apply potential to the motor I3 whereupon the motor is energized and reciprocates the crosshead 25 along the slide 26.

As the crosshead 25 is driven to its lower position on the slide 25 the splice 63 is drawn around the periphery of the pulley 28 and assumes a position on the right hand side of the pulley directly above the crosshead slide 26, and the weight 41 is raised to its uppermost position on the guide 46. On the return stroke of the crosshead 25 the splice 63 passes back over the periphery of the pulley 28 and assumes its normal starting position on the left hand side of the pulley, and the weight 34 returns to its lowermost position. At the same time the round-headed bolt 16 has made a complete revolution and actuated the operating arm 82 of the microswitch 8i) thereby closing the D. C. circuit to the coil I55 of the step selector I46, whereupon the arms I31 and I6I are advanced to their respective No. 1 positions. As the bolt 16 of the ring 15 passes over the operating arm 82 of the microswitch 80, the D. C. circuit to the coil I55 is opened and the arms I31 and I6I remain in their advanced position.

The motor I3 continues to reciprocate the crosshead 25 until the bolt 16 makes five complete revolutions and actuated the microswitch 80 five times, at which point the arms I31 and IGI of the step selector I40 have been advanced to their respective final contacting positions. The arm I31 now engages the final contact MI and closes the circuit to the coil I3I of the relay I2I and thereby energizes the relay 2I which opens its contact I26 and closes its contact I21. When the contact I20 has been thus actuated, the holding circuit for the coil I22 is broken whereby the relay I23 is deenergized. The contacts I16I16 of the relay I23 are thereby opened and disconnect the motor I3 from the source of potential whereupon the flexing apparatus is no longer operated. When the arm I6I bridges across the final contacts I58 and I69, the D. C. circuit to the coil I55 is maintained through the contact arm I51 and is supplied directly from the Junetion I62 and the resistor I54. At this point the coil is energized until it opens the contact arm I51, whereupon the arms I31 and I6I advance another step. The spring I61 recloses the contact arm I51 and the coil I55 is again energized whereby the arms I31 and I6I are advanced another step. The step selector I46 continues to operate in this manner until the arms I31 and IGI return to their normal starting positions. However, the relay I2I remains energized through its hold-in contact I21 and another flexing operation cannot be initiated until the push button 93 is actuated so that its contact I25 is momentarily opened thereby breaking the holding circuit of the coil I3I. When the arms I31 and I6I are returned to their normal starting positions, they do not interrupt their associated control circuits while they are energized due to the fact the contact arm I51 has previously opened the D; C. circuit to the coil I55 and the contact I21 of the relay I2I is held in a closed position maintaining the coil I3I energized even though the arm I31 has been withdrawn from its final contact MI.

The splice 63 of the spliced cable 60 has now been flexed ten times due to the automatic operation of the flexing apparatus and is, therefore, ready to be removed therefrom. During the flexing operation the operator is required to hold the push button 92 in a closed position in order to determine whether the butt-welded joints within the Splice 63 remain intact during the flexing operation, which fact is indicated by the lamps 9I9I. In other words, should any one of the lamps 9I9I be darkened during the flexing operation, it would indicate that one of the welded joints within the splice 63 has been broken and caused to separate during the fiexing operation.

After the motor I3 has been automatically stopped by the intermittent operation of the step selector I40, the push button 92 is released and the spliced cable 60 removed from the testing apparatus so that another spliced cable may be positioned thereon and connected to the test set as described above. The splice of the cable now positioned on the apparatus is subjected to the plurality of fiexing operations like that described for the cable 60.

While the above described apparatus is particularly adapted to test and fiex cable splices of the type described, it is to be understood that it may be modified to test other types of cable splices and other types of cables without departing from the scope of the invention as defined in the appended claim.

What is claimed is:

An apparatus for testing cable splices of multiconductor cables, which comprises an upright support, a crosshead guide mounted on the support, a crosshead slidably positioned in the crosshead guide, a crank, means for connectin the crosshead to the crank, a motor for rotating the crank, a weight guide mounted in an upright position at the base of the upright support, a weight slidably positioned in the weight guide, a pulley rotatably mounted on the upper end of the upright support over which a spliced cable to be tested may be looped so that a splice therein is adjacent to the pulley, quickly operable means for connecting a portion of the cable on one side of the splice to the crosshead, quickly operable means for connecting a portion of the cable on the other side of the splice to the weight, manually operable means for lifting the weight above the bottom of the guide when the cable is con- 9 nected thereto so that the weight is supported by the cable when the lifting means is released and thereby tensions the cable splice, means for energizing the motor to drive the crank and thereby draw the splice back and forth around the pulley under the tension of the Weight, a cam driven by the crank, and means operable by the cam for stopping the motor after the cable splice is drawn back and forth over the pulley a predetermined number of times.

CLAY E. LEWIS.

REFERENCES CITED The following references are of record in the file of this patent:

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